Gran Telescopio Canarias (GTC) has one of the largest mirrors of any visible and infrared light telescope. Its primary (main) mirror measures 34 feet (10.4 meters) in diameter. The GTC sits atop a 7,900-foot (2,400-meter) mountain on the island of La Palma in Spain’s Canary Islands. A partnership of Spain, Mexico, and the University of Florida built the telescope and operates it.
The GTC is a reflecting telescope, a telescope that uses mirrors to collect and focus light. Its primary mirror consists of 36 individual curved glass hexagons, fitted together to form a single curved surface. Two smaller mirrors, known as the secondary and tertiary mirrors, direct light collected by the primary mirror to one of several specialized cameras.
Two of the GTC’s cameras are called OSIRIS and CanariCam. OSIRIS is a visible-light camera and spectrograph. A spectrograph is a device that can spread light into a rainbowlike band of wavelengths called a spectrum (plural, spectra). Scientists study the spectra of distant objects to learn about their motion, shape, and chemical composition. CanariCam detects infrared radiation. It can function as an infrared camera and spectrograph.
Construction of the GTC began in 2000. The telescope recorded its first observations on July 13, 2007. On July 24, 2009, King Juan Carlos and Queen Sofia of Spain officially opened the telescope in a ceremony marking the completion of the construction.
